Solve for $x$ and $y$ using elimination. ${x+3y = 19}$ ${-x-2y = -16}$
Explanation: We can eliminate $x$ by adding the equations together when the $x$ coefficients have opposite signs. Add the equations together. Notice that the terms $x$ and $-x$ cancel out. ${y = 3}$ Now that you know ${y = 3}$ , plug it back into $\thinspace {x+3y = 19}\thinspace$ to find $x$ ${x + 3}{(3)}{= 19}$ $x+9 = 19$ $x+9{-9} = 19{-9}$ ${x = 10}$ You can also plug ${y = 3}$ into $\thinspace {-x-2y = -16}\thinspace$ and get the same answer for $x$ : ${-x - 2}{(3)}{= -16}$ ${x = 10}$